diff --git a/article/serializers.py b/article/serializers.py
index 1f913a5..bfb6a24 100644
--- a/article/serializers.py
+++ b/article/serializers.py
@@ -14,7 +14,8 @@ class ArticleCommentSerializer(ModelSerializer):
     parent_user_name = SerializerMethodField()
     replies = SerializerMethodField()
     is_liked = SerializerMethodField()
-    created_at = DateTimeField(format='%Y-%m-%d %H:%M')
+    # read_only=True 必须字段级声明：DRF/adrf 的 Meta.read_only_fields 对显式声明字段无效
+    created_at = DateTimeField(format='%Y-%m-%d %H:%M', read_only=True)
 
     class Meta:
         model = ArticleComment